In communications systems, such as wireless, wireline, LAN, WAN, WIMAX, Blue Tooth wireless mobile communications systems, etc., many devices need to utilize various resources, such as communications network elements, base stations, networks, communications media, etc., where a plurality of devices contend or compete for a given resource or pool of resources. In addition, modern Evolution Data Only (EVDO) EVDO Rev. A and other communications systems may provide for multiple levels of device priority (priority classes), where access to shared resources is provided in prioritized fashion, with devices of a higher priority class receiving preferential utilization compared with lower priority devices. In systems having a single or multiple priority levels, resource contention can occur when multiple devices attempt to simultaneously access a resource such that the input handling capacity of the resource is exceeded (access attempt collision failure), or when the resource is operating at maximum capacity and is unable to service any additional information from one or more devices (utilization attempt failure). For instance, to initiate a call in an EVDO Rev. A wireless network, mobile communications devices, such as cell phones, PDAs, portable computers, etc., compete for access to a local base station serving a given area or location to communicate with the base station over an access channel. In this case, the base station periodically sends a broadcast message to all devices in the area, which identifies the access channel to be used for setting up a call. Contention arises when two or more mobile units simultaneously attempt to access the base station on the access channel, leading to a collision of the call initiation messages. Resource utilization contention occurs when contention for a shared resource with limited utilization or loading capabilities causes some attempts for utilization to fail (e.g., dropped data packets).
In many communications systems, the accessing devices include functionality to allow the device to retry a failed access attempt, known as apersistence. In conventional Multiple Access Collision Detection (MACD) bus arbitration systems, devices connected to a common bus resource will initiate data transfer in an asynchronous fashion and will listen to the bus to detect if a collision occurred. If so, each device involved in the collision will wait for a random time and then retry the transfer. In this type of system, the device apersistence is therefore random in nature, with the individual devices generating the random time value internally. In other systems with shared resources, the devices perform an apersistence test using apersistence property information received from the resource of contention. For instance, the devices in an EVDO environment will be synchronized with the base station to selectively attempt access at discrete times, where the devices internally perform an apersistence test using an apersistence property value broadcast by the base station. The devices derive an apersistence number from the apersistence property value received from the base station, and compare the apersistence number to a randomly generated value in each access cycle, whereby the decision on whether to attempt a utilization by the device is determined by information received from the resource of contention. In these systems, the resource typically adjusts the value of the apersistence property so as to reduce the likelihood of a given device passing the apersistence test when the current resource load is high. However, this leads to an increasing accumulation of devices failing the apersistence test, which carry over into the next access cycle, where the apersistence test is then subjected to this carryover as well as any incoming devices attempting to access the resource of contention, eventually leading to sub-optimal resource utilization. Accordingly, there is a need for improved methods and systems for controlling utilization of shared resources by which the accumulation of devices failing an apersistence test can be alleviated in a communications system.